Hi all,
anyone had cracked solder joints with even lead lifting with Quadpaks AND 
conformal coating? What was the reason? Vibration, mechanical shock, 
tempcycling, warpage, thermal mismatch, voiding, diffusion, Kirkendall or 
what?  The coating is robotic dispensed and the Quadpak is 'drowned' in 
coating in order to secure the leads against vibration. Personally, I 
dislike the abundant lot of coating. Am afraid that, at minus degrees, the 
coating gets hard and less ductil. When the processor is energized and warms 
up quickly (airgap between Quad and board), maybe the still-at-minus coating 
(with its low heat conduction) won't match the thermal expansion of the 
Quad. FEM is done and says no such problems, but FEM isn't the a saviour 
always!

Inge 

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